How Does Caffeine Affect the Body?

For some, that jolt of fresh brewed coffee is an instant refresher, awakening the mind and body from a long, deep sleep. However, this isn't the case for everyone, as some people find that caffeine affects the body in unfortunate, disrupting ways, and such effects can reduce productivity and stamina as the day progresses. Knowing if you're a victim to your daily sumatra blend and should instead stick with non-caffeinated brews, teas, or even, plain water, can save you time and energy in getting your morning started on a high note. Here are a few things you should know about how caffeine affects the body as well as how to determine whether you should lower your caffeine intake for good.

How exactly does the body process caffeine? Matt Swenson, Director of Coffee at Chameleon Cold-Brew, explains the effects on your nervous system. "Generally, when we get tired, the body begins to release adenosine. These molecules bind to adenosine receptors to tell your body to start winding down and gives the general feeling of tiredness. Caffeine, structurally similar to adenosine, binds to the receptors instead and acts as a stimulant by activating the central nervous system and producing heightened brain activity." Swenson recommends a cold-brew to get the day started (or get through that afternoon slump, right?).

Plus, it can differ based on your predisposition for caffeine tolerance, lifestyle circumstances, and metabolism. "Some people metabolize caffeine slowly and therefore are more likely to experience the negative side effects [of caffeine]. People who are already dealing with anxiety may feel worse with caffeine intake," Chong says. Additionally, "because it stimulates gastric acid secretion, caffeine can worsen symptoms of gastroesophageal reflux disease (GERD)" and since "it stimulates the heart muscle and causes blood vessel constriction, it can lead to an increase in blood pressure. This is usually not a problem for someone without high blood pressure, but can make pre-existing high blood pressure more difficult to control."

After evaluating if you're OK with caffeine intake, consider the dosage. "This is definitely one of those substances in which we can say 'the dose makes the poison.' Caffeine overdose can be fatal. And unfortunately because of individual tolerance levels, no one can say for sure at what dose you will feel adverse effects. Most experts feel up to 400mg per day is safe for most people. Powdered caffeine and energy drinks can be dangerous because of their high caffeine content," cautions Chong.

Though we've weighed the cons, what are the pros? "Because it causes blood vessel constriction, caffeine has been helpful in treating or preventing headaches," Chong says. It also improves your athletic performance.